Grinding machine



p 1937- c. G. FLYGAR: 2,077,359

GRINDING MACHINE Filed April 8, 1936 llll CARI. G.FLYG'ARE Patented Apr. 13, 1937 GRINDING MACHINE Carl G. Flygare, Worcester, Mass., assignor to Norton Company, Worcester, Mass., a corporation of Massachusetts Application April 8, 1936, Serial No. 73,193

5 Claims.

This invention relates to grinding machines, and more particularly to a grinding apparatus for grinding a partial cylindrical surface.

I It is the primary object of this invention to provide a simple, thoroughly practical grinding apparatus for grinding a partial cylindrical sur- 5 cylindrical surface being ground may be varied according to the work piece to be ground. Other objects will be in part obvious or in part pointed out hereinafter.

This invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing, in which is 25 shown one of various possible embodiments of the mechanical features of this invention,

Figure 1 is a fragmentary cross sectional view through a grinding machine showing the improved grinding apparatus, having parts broken away to more clearly show the construction;

Figure 2 is a fragmentary longitudinal section taken approximately on the line 22 of Figure 1, showing the supporting and driving mechanism f the work piece;

Figure 3 is a fragmentary cross sectional view through a grinding machine showing the wheel feeding mechanism;

Figure 4 is a fragmentary sectional view taken approximately on the line 4--4 of Figure l, on an enlarged scale; and

Figure 5 is a fragmentary cross sectional view, on an enlarged scale, taken approximately on the line 5-5 of Figure 1, showing the adjustment of the throw of the driving member.

A grinding machine has been illustrated in the drawing comprising a base I!) which supports a transversely movable wheel slide ll thereon. The wheel slide H is mounted for a transverse movement on V and flat ways (not shown) in a manner similar to that shown in the expired U. S. Patent to Norton No. 762,838 dated June 14, 1904. The wheel slide ll supports a rotatable grinding wheel l2 on a rotatable wheel spindle 55 I3. Thewheel spindle l3 may be rotated-from any well-known source of power, by means of a driving belt H which wraps around a driving pulley l5 mounted on the outer end of the wheel spindle l3.

Work table traverse The base ID also supports a longitudinally reciprocable work supporting table I8 on a V-way l9 and a fiat way 20. The table l8 serves to rotatably support a work piece 23 having a partial cylindrical surface 24 to be ground. The table 18 is arranged so thatit may be traversed or reciprocated longitudinally either manually or by power by any of the well-known table traversing or reciprocating mechanisms which are common practice in the art. As illustrated in the drawing, a. manually operable traverse mechanism has been illustrated comprising a manually operable traverse wheel 26 mounted on the outer end of a shaft 21 which is rotatably supported in a bearing 28 which is fixed to the base Ill. The shaft 21 carries a gear 29 on its inner end which meshes with a rack bar 30 depending from the under side of the table i8. By rotation of the manually operable traverse wheel 26, the table l8 may be moved longitudinally relative to the base l0 either for positioning the work longitudinally relative to the operative face of the grinding wheel or for use in a traverse grinding operation.

Wheel feed The wheel slide ll may be fed transversely relative to the base ID by means of a half nut 32 and a rotatable feed screw 33 which is rotatably supported in bearings (not shown)- in the base l0. These parts have not been illustrated in detail since they are not considered part of the present invention. For further details of the nut and screw feed mechanism, reference may be had to the above-mentioned patent to Norton No. 762,838. The outer end of -the feed screw 33 carries a gear 34 meshing with a gear 35 which is mounted on the inner end of a rotatable shaft 36. The shaft 36 is supported in bearings (not shown) in the base It) and carries at its outer end a gear 31 meshing with a gear 38 mounted on the inner end of a rotatable shaft 39'. The outer end of the shaft 39 carries a manually operable feed wheel 40 which is connected by a micrometer adjusting device 4| with a gear 42 mounted on the outer end of the shaft 39. By rotation of the hand wheel 40, the gears 38, 31, 35, 34 may be turned to rotate the feed screw 33 and thereby cause the half nut 32, the wheel slide II and the grinding wheel l2 to be moved trans- Work supporting and oscillating mechanism 5 The work piece 23 to be ground is preferably supported between a headstock center 45 and a footstock center 46 (Figure 2). The headstock center 45 is supported by a headstock 41 which together with therfootstock (not shown) are supported on a swivel table 48 which is in turn supported on the upper surface of the longitudinally movable table l8.

In order to obtain one of the main objects of this invention, it is desirable to provide a suit-- able mechanism for oscillating or rotating the work piece through a partial rotation so that the grinding wheel may grind a partial cylindrical surface on the .work piece 23. An electric motor 49 is mounted on the headstock 41 and is provided with a rotatable armature shaft 58 carrying a worm 5| which meshes with a worm gear 52 mounted on a rotatable shaft 53. The shaft 53 carries a crank arm 54 which supports a crankpin 55 on its outer end. The crankpin 55 is provided with a reduced portion 56 which rotatably supports an end block 51 of an adjustable connecting rod 58. The other end of the connecting rod 58 is provided with an end block 59 which is adjustably connected to a crank arm 60 which is keyed to the outer end of a shaft 6!. The central portion of the connecting rod 58 is formed as a right and left-hand screw member 63, the

opposite ends of which are screw threaded into the end blocks 51 and 59, and is arranged to be locked in adjusted position by means of a lock nut 64. By adjusting the right and left-hand screw member 53, the center distance between the crankpin 55 and a crankpin 66 mounted on the end block 59 may be adjusted either toward or from each other to vary the length of the connecting rod so as to adjust the position of the crank arm 66 relative to the crankpin 55.

The crankpin 66 is supported in a slide block 61 which is provided with a slabbed-off portion 68. The slabbed-off portion 68 slidably fits within an elongated slot 69 in the lever 60. The block 61 may be readily adjusted within the elongated slot 89 by means of an adjusting screw 10 which is screw threaded into the upper portion ll of the lever 68 and is provided with a head 12 at or lowered, thereby varying the crank arm between the axis of the crankpin 66 and the axis of the shaft 6|. When the block 61 has been adjusted to the desired position, the block may be locked in adjusted position by means of a nut 15 threaded onto a portion it on the end of the 0 crankpin 66 which serves to clamp a thrust Washer 11 to lock the block 61 in adjusted'posltion relative to the crank arm 80.

The shaft 6| carries at its other end a gear 80 which meshes with a gear 8| mounted on the 5 outer end of a headstock spindle 82, the other end of which supports the headstock center 45. The headstock spindle 82 is provided with a work driving member 83 which is provided with a driving pin 84. The driving pin 84 is arranged to engage a portion of the work piece. In the present case the work piece is provided with a hole 85 within which the driving pin 84 fits.

Operation The operationof this apparatus'is readily apparent from the foregoing disclosure. A work piece 23 is mounted in place on the headstock center 45 and the footstock center 46 with the work driving pin 84 engaging hole in the work piece 23. The electric motor 49 may then be set 5 in operation by means of power from the power lines by closing a switch 9| to start the rota-v tion of the motor. The motor 49 drives through .the worm 5| and worm gear 52 to rotate the crank arm 54 which serves to transmit a crank 10 motion through the adjustable connecting rod 58 to transmit a rocking movement to the crank arm 60 which in turn transmits a corresponding movement through the gear 80 and gear 8| to oscillate the work piece 23 through a partial 15 turn. The extent of oscillation of the work piece 23 may be adjusted by varying the position of the crankpin 66 relative to the crank arm 60, and the position of the oscillating motion may be ad justed by varying the length of the connecting 2o rod 58, as above described. After the abovementioned adjustments have been made, the grinding wheel l2 may be fed into engagement with the work piece 23 to grind the partial cylindrical surface 24 by rotating the manually oper- 25 able feed wheel 40. If the machine is arranged for grinding by the plunge-cut method, the wheel is of sufiicient width to grind the entire length of the surface to be ground so that the wheel may be fed directly toward the work axis to grind 30 the surface to the desired extent.

If, however, a traverse grinding operation is to be performed, the wheel is fed toward the work piece by means of the manually operable feed wheel 40, and the table i3 is traversed longitudi- 35 nally relative to the base it] by rotation of the manually operable traverse wheel 26 to traverse the work piece across the operative face of the grinding wheel.

It will thus be seen that there has been pro- 40 vided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of theabove invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.

I claim:-

1. A grinding machine comprising a transversely movable rotatable grinding wheel, means to feed the wheel transversely to produce a grinding feed, a longitudinally movable work supporting table, means to traverse said table longitudinally, means to rotatably support a work piece on said table, a work driving mechanism arranged to oscillate the work con- 60 tinuously through a partial rotation to grind a partial cylindrical surface on the work piece, means to vary the position of oscillation of the work support relative to the work piece, and means to adjust the extent of oscillation thereof. 65

2. A grinding machine comprising a transversely movable rotatable grinding wheel, a longitudinally movable work supporting table, a rotatable work support on said table, means to feed the wheel transversely toward and from the work 7 support to produce the desired feeding action between the wheel and work piece, means including head and footstock centers to rotatably support a work piece having a partial cylindrical surface to be ground, means to traverse said work support 75 longitudinally to position the work piece in operative relation with the grinding wheel, and an adjustable oscillating mechanism to oscillate the work piece through a partial turn while in operative contact with the grinding wheel to grind a partial cylindrical surface thereon.

3. A grinding apparatus tor grinding a partial cylindrical surface including a rotatable grinding wheel, means to feed said wheel transversely toward and from the work support to produce the desired feeding action between the wheel and work piece, a rotatable work support, a work driving mechanism including an electric motor, a reduction gearing connected to be rotated by said motor, a crank arm rotated thereby, an adjustable connection rod, 9. second crank arm, and geared connections between said second crank arm and said rotatable work support whereby the work piece may be oscillated continuously 2 through a predetermined partial rotation.

4. A grinding machine for grinding a partial cylindrical work piece including a rotatable grinding wheel, a rotatable work support including a head and footstock center, a longitudinally 25 movable work supporting table therefor, means to traverse said table longitudinally, means to rotate a work piece mounted thereon including an electric motor, a crank arm rotated by said motor, geared connections between said crank arm and the rotatable work support whereby the work support may be continuouslyoscillated during the grinding operation, and adjusting means interposed between said motor and said geared connections whereby the extent of oscillation of said work piece may be varied.

5. A grinding machine comprising a transversely movable rotatable grinding wheel, means to feed said 'wheel transversely, a longitudinally movabl work supporting table, means to traverse said table longitudinally, means including a head and rootstock center on said table rotatably to support a work piece thereon, a work driving mechanism including an electric motor, a crank .arm rotated by said motor, a second crank arm,

geared connections between said second crank arm and said rotatable work support, an adiust able connecting rod connecting said crank arm and the second crank arm, and means to adjust the length of said connecting rod and the effective length of said second crank arm to vary the position and extent of oscillation of the work support as desired.

CARL G. FLYGARE. 

